Closure device for a container and a container equipped with one such device

ABSTRACT

The invention relates to a closure device ( 1 ) for a container. The inventive device comprises a cover ( 2 ) which is equipped with an inner skirt ( 24 ) that can rest against the internal radial surface (G 2 ) of the neck (G) of a bottle (B). The base ( 23 ) of the cover ( 2 ) is provided with a first layer ( 5 ) of material which is impervious to one or more pre-determined gases and a second layer ( 6 ) which covers the first layer and which is made from a material that can absorb one or more pre-determined gases, preferably an oxygen-absorbing material.

The invention relates to a device for closing a container and to a container equipped with such a device.

It is known to make containers for liquid, such as bottles for drinks, by extrusion/blowing or injection/blowing of plastics material. It is known to equip such bottles with a stopper likewise made of plastics material. It is essential that such containers be closed hermetically with a view to allowing prolonged storage of the products that they contain. In order to ensure a satisfactory seal, it is known, for example by GB-A-2 013 635, to provide an annular skirt intended to come into tight abutment against the internal radial face of the neck of a bottle.

However, when used with a bottle containing a carbonated drink, carbon dioxide (CO₂) may be released, capable of leading to an increase of pressure in is the neck of the bottle. It is known, for example by U.S. Pat. No. 4,279,350, to place on the internal face of a stopper a product absorbing the oxygen (called “oxygen scavenger”). Up to the present time, it has been considered that the use of such an oxygen-absorbing material made it possible to render a stopper globally tight with respect to the neck of a bottle, and to do without a sealing skirt.

Furthermore, it is known from US-A-2002/0000420, to provide, on the same face of a stopper and in two separate zones, an oxygen absorbing material and a sealing joint intended to receive in abutment the upper edge of the neck of a bottle. This prior art assumes that the risks of leakage are localized in the zone of abutment of the neck on the stopper.

The invention does the opposite of these approaches by proposing a stopper provided with a sealing skirt and which makes it possible to adapt to the presence of oxygen or another gas in its vicinity.

In addition, certain bottles contain products which are very sensitive to oxygen and which may spoil rapidly if the stopper allows the oxygen from the ambient air to enter.

The invention proposes to solve the problem of tightness of the closure device by distinguishing the gases by their nature, and by responding thereto by solutions adapted to each of them.

The invention relates to a closure device for a container provided with a neck, this device comprising a stopper provided with an inner skirt adapted to come into abutment against the internal radial surface of this neck and, at the level of its base, with a first layer of material impermeable to one or more predetermined gases and with a second layer made of a material adapted to absorb one or more predetermined gases, preferably a material adapted to absorb the oxygen, characterized in that the first and second layers are arranged, with respect to the base of the stopper, so that one of them covers the other.

Thanks to the invention, the inner skirt performs its role of tight abutment against the internal surface of the neck efficiently, in particular concerning the tightness with respect to CO₂, while the combination of the first and second layers makes it possible to absorb the oxygen coming from the product located in the container, the first layer making it possible to isolate the second layer from the outside, with the result that the absorbent material does not risk being saturated by a gas traversing the base of the stopper. In practice, one of the layers may cover the other directly or indirectly, i.e. with the interposition of matter, particularly the material of the base of the stopper.

According to advantageous but non-obligatory aspects of the invention, a closure device may incorporate one or more of the following characteristics:

-   -   the first and second layers extend at least at the level of a         part of the base located radially inside the sealing skirt.     -   The first and second layers are affixed on the internal face of         the base of the stopper, the second layer covering the first. In         that case, it may be provided that the internal face of the         stopper be provided with a rib defining a volume for receiving         the afore-mentioned first and second layers.     -   The first layer is formed on an external face of the base of the         stopper, while the second layer is formed on an internal face of         the stopper, the first layer covering the second with the         interposition of the base of the stopper. The gas-impermeable         barrier may thus be constituted by a coating outside the         stopper.     -   The second layer is disposed radially inside the skirt. In this         way, this second layer does not come into direct contact with         the neck and does not risk being crushed or sheared thereby.     -   The first and second layers are formed by different materials.     -   The first layer comprises a silica oxide, a varnish or a         lacquer, or is made by metallization.

Finally, the invention relates to a container for liquid, for example a bottle made of plastics material, equipped with a closure device as described previously. Such a container makes it possible to store, for a relatively long period and without risk of alteration, the product that it contains, particularly a carbonated drink.

The invention will be more readily understood and other advantages thereof will appear more clearly in the light of the following description of the two forms of embodiment of a closure device in accordance with its principle, given solely by way of example and made with reference to the accompanying drawings, in which:

FIG. 1 is an axial section of a closure device in accordance with the invention mounted on the neck of a bottle in accordance with the invention.

FIG. 2 is a view on a larger scale of detail II in FIG. 1, and

FIG. 3 is a view similar to FIG. 1 for a closure device in accordance with a second form of embodiment of the invention.

The closure device 1 shown in the Figure comprises a stopper 2 connected to a tamper-evident band 3 by a breakable part 4.

The device is provided to be mounted on the neck G of a bottle B, this neck being provided with an external thread G₁, while the stopper is provided with an internal thread 21 of corresponding shape.

22 denotes the base of the stopper 2. On its internal face 23, i.e. its face turned towards the inside of the neck G, the base 22 is provided with a skirt 24 centred on the axis of symmetry X-X′ of the device 1 and presenting an external bead 25 provided to come into abutment against the internal radial surface G₂ of the neck G.

An annular rib 26 is formed on the face 23, being centred on axis X-X′. This rib defines a zone Z₂₆ in the form of a disc in which are affixed two layers 5 and 6 on the face 23 of the base 22. The first layer 5 is constituted by ethylene vinyl alcohol (EVOH) and is deposited on the face 23 by any appropriate process. The second layer 6 is formed in a material absorbing oxygen, for example as described in U.S. Pat. No. 4,279,350.

In practice, the layer 6 may be overmoulded in the zone Z₂₆ once the layer 5 has been placed in position, which makes it possible to efficiently maintain the layer 5 in position. In that case, it may be question, for example, of iron in pulverulent form, of compounds including iron, such as iron salts, ascorbic acid or cobalt stearate. If the layer 6 is made in the form of a disc fixed on the base 22, it may be made of glucose oxydase and/or glucose catalase in order to reduce the free oxygen present in the neck G by an “enzymatic” method.

Thanks to the first layer 5, the second layer 6 is protected with respect to the oxygen located outside the device 1, with the result that the layer 6 does not risk being saturated with oxygen to the point of not being able efficiently to absorb the possible gaseous emissions coming from the liquid contained in the bottle B.

As the layers 5 and 6 are confined in the circular volume defined by the rib 26, these layers do not interfere with the neck G and do not risk being crushed or torn, particularly at the end of screwing or at the beginning of unscrewing of the stopper 2.

In the second form of embodiment of the invention shown in FIG. 3, the elements similar to those of the first embodiment bear identical references increased by 100. The device 101 of this embodiment comprises a stopper 102 connected to a tamper-evident band 103 by a breakable part 104. This device differs from the preceding one in that the first, oxygen-impermeable layer 105 is formed by a coating affixed on the external surface 128 of the base 122 of the stopper 102, while the second layer 106 is affixed against the internal face 123 of this bottom 122. The layer 105 thus covers the base 122 of the stopper 102 which itself covers the layer 106.

As previously, a skirt 124 provided with a bead 125 comes into abutment against the neck G of a bottle B, while the layer 106 can efficiently absorb the oxygen contained in the neck G, as it is isolated from the outside atmosphere both by the skirt 124 and by the layer 105.

The layers 105 and 106 extend in particular over the whole central zone of the base 122, i.e. that part of the base located radially inside the skirt 124.

The coating layer 105 may comprise a silica oxide, a varnish or a lacquer. It may also be made by metallization.

The layers 5 and 105 might equally well be made of polyvinyl chloride (pvc), polyvinylidene chloride (pvdc), ethylene vinyl alcohol (evoh), polyamide (pa), polyethylene naphthalate (pen), polyvinyl alcohol (pva), acrylate copolymer of polyacrylnitrile (pna) type, polymethylmethacrylate (ppma), butadiene copolymer, styrene, bi-oriented polypropylene (bopp) or of a mixture based on these products. 

1. Closure device for a container provided with a neck, said device comprising a stopper (2; 102) provided with an inner skirt (24; 124) adapted to come into abutment against the internal radial surface (G₂) of said neck (G) said device being provided, at the level of the base (22; 122) of said stopper (2; 102), with a first layer (5; 105) of material impermeable to one or more predetermined gases and with a second layer (6; 106) made of a material adapted to absorb one or more predetermined gases, preferably a material adapted to absorb the oxygen, characterized in that said first and second layers (5, 6; 105, 106) are arranged, with respect to the base (22; 122) of said stopper, so that one of them (6, 105) covers the other (5, 106).
 2. Device according to claim 1, characterized in that said first and second layers (5, 6; 105, 106) extend at least at the level of a part (Z₂₆) of said base (22; 122) located radially inside said skirt (24; 124).
 3. Device according to claim 1, characterized in that said first and second layers (5, 6) are affixed on the internal face (23) of said base (22), said second layer covering said first layer.
 4. Device according to claim 3, characterized in that said internal face (23) is provided with a rib (26) defining a volume (Z₂₆) for receiving said first and second layers (5, 6).
 5. Device according to claim 1, characterized in that said first layer (105) is formed on an external face (128) of said base (122), while said second layer (106) is formed on an internal face (123) of said base, said first layer (105) covering said second layer (106) with the interposition of said base (122).
 6. Device according to claim 1, characterized in that said second layer (6; 106) is disposed radially inside said skirt (24; 124).
 7. Device according to claim 1, characterized in that said first and second layers (5, 6; 105, 106) are formed by different materials.
 8. Device according to one of the claim 1, characterized in that said first layer (5; 105) is made of polyvinyl chloride (PVC), polyvinylidene chloride (PVDC), ethylene vinyl alcohol (EVOH), polyamide (PA), polyethylene naphthalate (PEN), polyvinyl alcohol (PVA), acrylate copolymer of polyacrylnitrile _(PNA) type, polymethylmethacrylate (PPMA), butadiene copolymer, styrene, bi-oriented polypropylene (BOPP) or of a mixture based on these products.
 9. Device according to claim 1, characterized in that said first layer (5; 105) comprises a silica oxide, a varnish or a lacquer or is made by metallization.
 10. Container for liquid, particularly bottle (B) made of plastics material, equipped with a closure device (1; 101) according to claim
 1. 